Treatment with anti-RANKL antibody reduces infarct size and attenuates dysfunction impacting on neutrophil-mediated injury.

Selective pharmacological treatments targeting reperfusion injury produced modest protective effects and might be associated with immunosuppression. In order to identify novel and better-tolerated approaches, we focused on the neutralization of receptor activator of nuclear factor kappa-B ligand [RANKL], a cytokine recently shown to activate inflammatory cells (i.e. neutrophils) orchestrating post-infarction injury and repair. Myocardial ischemia (60min) and reperfusion injury was surgically induced in C57Bl/6 mice. In hearts and serum, RANKL was early upregulated during reperfusion. A "one-shot" injection with neutralizing anti-RANKL IgG during ischemia ameliorated myocardial infarct size and function, but not adverse remodeling (determined by Magnetic Resonance Imaging [MRI]) as compared to Vehicle or control IgG. These beneficial effects were accompanied in vivo by reduction in cardiac neutrophil infiltration, reactive oxygen species (ROS) and MMP-9 release. Anti-RANKL IgG treatment suppressed sudden peak of neutrophil granule products in mouse serum early after reperfusion onset. In vitro, RANK mRNA expression was detected in isolated mouse neutrophils. Co-incubation with neutralizing anti-RANKL IgG abrogated RANKL-induced mouse neutrophil degranulation and migration, suggesting a critical role of RANKL in neutrophil-mediated injury. Conversely, anti-RANKL IgG did not affect salvage pathways in cardiac cells (i.e. ERK p42/p44, Akt and STAT-3) or macrophage cardiac infiltration. Finally, treatment with anti-RANKL IgG showed no effect on B and T lymphocyte polarization (in serum, spleen and infarcted myocardium) and circulating chemokines as compared with Vehicle or control IgG. In conclusion, acute treatment with anti-RANKL IgG improved cardiac infarct size and function by potentially impacting on neutrophil-mediated injury and repair.

Inferior vena cava parameters predict re-admission in ischaemic heart failure.

BACKGROUND: The clinical history of heart failure (HF) is usually characterized by frequent hospitalizations for decompensation. Therefore, several markers of subclinical hemodynamic congestion are under investigation for predicting early rehospitalization. In this field, the potential of ultrasound inferior vena cava (IVC) assessment has been recently investigated in HF but not yet assessed in the different aetiological categories. MATERIAL AND METHODS: Forty-eight patients admitted for decompensated HF (n = 25 with ischaemic heart disease [IHD] and n = 23 non-IHD) underwent biochemical examination (including NT-proBNP), echocardiography and IVC assessment by hand-carried ultrasound (HCU). During 60-day follow-up after discharge, the re-hospitalization rate for HF was recorded to investigate the predictive power of NT-proBNP and IVC assessment among the two study groups. RESULTS: IHD and non-IHD patients with HF were similar except for gender distribution. During follow-up, 16·7% of patients were rehospitalized for decompensated HF, with higher prevalence in IHD group (28% vs. 4·3% P = 0·031). IVC assessment at discharge significantly predicted re-admission in the overall population and in IHD group, whereas NT-proBNP failed to predict rehospitalization in IHD group. In adjusted hazard ratio, only IVC min and the changes of IVC from admission significantly predicted re-admission. ROC analysis confirmed the change in IVC min as the best predictor of rehospitalization in patients with IHD. CONCLUSION: This pilot study showed a higher early re-admission rate in patients with HF due to IHD. In addition, the change in IVC min diameter from admission to discharge was the best predictor of re-admission in patients with IHD.

Statin treatment is associated with reduction in serum levels of receptor activator of NF-κB ligand and neutrophil activation in patients with severe carotid stenosis.

Systemic and intraplaque biomarkers have been widely investigated in clinical cohorts as promising surrogate parameters of cardiovascular vulnerability. In this pilot study, we investigated if systemic and intraplaque levels of calcification biomarkers were affected by treatment with a statin in a cohort of patients with severe carotid stenosis and being asymptomatic for ischemic stroke. Patients on statin therapy had reduced serum osteopontin (OPN), RANKL/osteoprotegerin (OPG) ratio, and MMP-9/pro-MMP-9 activity as compared to untreated patients. Statin-treated patients exhibited increased levels of collagen and reduced neutrophil infiltration in downstream portions of carotid plaques as compared to untreated controls. In upstream plaque portions, OPG content was increased in statin-treated patients as compared to controls. Other histological parameters (such as lipid, macrophage, smooth muscle cell, and MMP-9 content) as well as RANKL, RANK, and OPG mRNA levels did not differ between the two patient groups. Serum RANKL/OPG ratio positively correlated with serum levels of neutrophilic products, intraplaque neutrophil, and MMP-9 content within downstream portions of carotid plaques. In conclusion, statin treatment was associated with improvement in serum RANKL levels and reduced neutrophil activity both systemically and in atherosclerotic plaques.

Impact of obesity and bariatric surgery on metabolism and coronary circulatory function.

Increases in intra-abdominal visceral adipose tissue have been widely appreciated as a risk factor for metabolic disorders such as dyslipidemia, hypertension, insulin resistance, and type 2 diabetes, whereas this is not the case for peripheral or subcutaneous obesity. While the underlying mechanisms that contribute to these differences in adipose tissue activity remain uncertain, increases in visceral fat commonly induce metabolic dysregulation, in part because of increased venous effluent of fatty acids and/or adipokines/cytokines to the liver. Increased body weight, paralleled by an increase in plasma markers of the insulin-resistance syndrome and chronic inflammation, is independently associated with coronary circulatory dysfunction. Recent data suggest that plasma proteins originating from the adipose tissue, such as endocannabinoids (EC), leptin, and adiponectin (termed adipocytes) play a central role in the regulation and control of coronary circulatory function in obesity. Positron emission tomography (PET) in concert with tracer kinetic modeling is a well established technique for quantifying regional myocardial blood flow at rest and in response to various forms of vasomotor stress. Myocardial flow reserve assessed by PET provides a noninvasive surrogate of coronary circulatory function. PET also enables the monitoring and characterization of coronary circulatory function in response to gastric bypass-induced weight loss in initially morbidly obese individuals, to medication and/or behavioral interventions related to weight, diet, and physical activity. Whether the observed improvement in coronary circulatory dysfunction via weight loss may translate to diminution in cardiovascular events awaits clinical confirmation.

Improvement in coronary circulatory function in morbidly obese individuals after gastric bypass-induced weight loss: relation to alterations in endocannabinoids and adipocytokines.

AIMS: To investigate the effect of surgical gastric bypass-induced weight loss and related alterations in endocannabinoids (ECs) and adipocytokine plasma levels on coronary circulatory dysfunction in morbidly obese (MOB) individuals. METHODS AND RESULTS: Myocardial blood flow (MBF) responses to cold pressor test (CPT) from rest (ΔMBF) and during pharmacologically induced hyperaemia were measured with ¹³N-ammonia PET/CT in 18 MOB individuals with a body mass index (BMI) > 40 kg/m² at baseline and after a median follow-up period of 22 months. Gastric bypass intervention decreased BMI from a median of 44.8 (inter-quartile range: 43.3, 48.2) to 30.8 (27.3, 34.7) kg/m² (P < 0.0001). This decrease in BMI was accompanied by a marked improvement in endothelium-related ΔMBF to CPT and hyperaemic MBFs, respectively [0.34 (0.18, 0.41) from 0.03 (-0.08, 0.15) mL/g/min, P = 0.002; and 2.51 (2.17, 2.64) from 1.53 (1.39, 2.18) mL/g/min, P < 0.001]. There was an inverse correlation between decreases in plasma concentrations of the EC anandamide and improvement in ΔMBF to CPT (r = -0.59, P = 0.009), while increases in adiponectin plasma levels correlated positively with hyperaemic MBFs (r = 0.60, P = 0.050). Conversely, decreases in leptin plasma concentrations were not observed to correlate with the improvement in coronary circulatory function (r = 0.22, P = 0.400, and r = -0.31, P = 0.250). CONCLUSIONS: Gastric bypass-related reduction of BMI in MOB individuals beneficially affects coronary circulatory dysfunction. The dysbalance between ECs and adipocytokines appears to be an important determinant of coronary circulatory function in obesity.

Role of mitogen-activated protein kinase pathways in multifactorial adverse cardiac remodeling associated with metabolic syndrome.

Metabolic syndrome has been widely associated with an increased risk for acute cardiovascular events. Emerging evidence supports metabolic syndrome as a condition favoring an adverse cardiac remodeling, which might evolve towards heart dysfunction and failure. This pathological remodeling has been described to result from the cardiac adaptive response to clinical mechanical conditions (such as hypertension, dyslipidemia, and hyperglycemia), soluble inflammatory molecules (such as cytokines and chemokines), as well as hormones (such as insulin), characterizing the pathophysiology of metabolic syndrome. Moreover, these cardiac processes (resulting in cardiac hypertrophy and fibrosis) are also associated with the modulation of intracellular signalling pathways within cardiomyocytes. Amongst the different intracellular kinases, mitogen-activated protein kinases (MAPKs) were shown to be involved in heart damage in metabolic syndrome. However, their role remains controversial. In this paper, we will discuss and update evidence on MAPK-mediated mechanisms underlying cardiac adverse remodeling associated with metabolic syndrome.

Update on the pathophysiological activities of the cardiac molecule cardiotrophin-1 in obesity.

Cardiotrophin-1 (CT-1) is a heart-targeting cytokine that has been reported to exert a variety of activities also in other organs such as the liver, adipose tissue, and atherosclerotic arteries. CT-1 has been shown to induce these effects via binding to a transmembrane receptor, comprising the leukaemia inhibitory factor receptor (LIFR ß ) subunit and the glycoprotein 130 (gp130, a common signal transducer). Both local and systemic concentrations of CT-1 have been shown to potentially play a critical role in obesity. For instance, CT-1 plasma concentrations have been shown to be increased in metabolic syndrome (a cluster disease including obesity) probably due to adipose tissue overexpression. Interestingly, treatment with exogenous CT-1 has been shown to improve lipid and glucose metabolism in animal models of obesity. These benefits might suggest a potential therapeutic role for CT-1. However, beyond its beneficial properties, CT-1 has been also shown to induce some adverse effects, such as cardiac hypertrophy and adipose tissue inflammation. Although scientific evidence is still needed, CT-1 might be considered as a potential example of damage/danger-associated molecular pattern (DAMP) in obesity-related cardiovascular diseases. In this narrative review, we aimed at discussing and updating evidence from basic research on the pathophysiological and potential therapeutic roles of CT-1 in obesity.

Quantitative PET/CT measures of myocardial flow reserve and atherosclerosis for cardiac risk assessment and predicting adverse patient outcomes.

Conventional scintigraphic myocardial perfusion imaging with SPECT/CT or with PET/CT has evolved as an important clinical tool for the diagnostic assessment of flow-limiting epicardial lesions and risk stratification of patients with suspected CAD. By determining the relative distribution of radiotracer-uptake in the left-ventricular (LV) myocardium during stress, the presence of flow-limiting CAD lesions can be identified. While this approach successfully identifies epicardial coronary artery lesions, the presence of subclinical and non-obstructive CAD may go undetected. In this direction, the concurrent ability of PET/CT to assess absolute myocardial blood flow (MBF) in ml/g/min, rather that relative regional distribution of radiotracer-uptake, and myocardial flow reserve (MFR), expands the scope of conventional myocardial perfusion imaging from the identification of more advanced and flow-limiting epicardial lesions to (1) subclinical CAD, (2) an improved characterization of the extent and severity of CAD burden, and (3) the discovery of "balanced" reduction in myocardial blood flow as a consequence of 3 vessel CAD. Concurrent to the PET data, the CT component of the hybrid PET/CT allows the assessment of coronary artery calcification as an indirect surrogate for CAD burden, without contrast, or with contrast angiography to directly denote coronary stenosis and/or plaque morphology with CT. Hybrid PET/CT system, therefore, has the potential to not only identify and characterize flow-limiting epicardial lesions but also subclinical stages of functional and/or structural stages of CAD. Whether the application of PET/CT for an optimal assessment of coronary pathology, its downstream effects on myocardial perfusion, and coronary circulatory function will in effect lead to changes in clinical decision-making process, investiture in preventive health care, and improved long-term outcome, awaits scientific verification.

Matching between regional coronary vasodilator capacity and corresponding circumferential strain in individuals with normal and increasing body weight.

BACKGROUND: To define the relationship between regional coronary vasodilator capacity and myocardial circumferential strain at rest in normal weight, overweight, and obese individuals with normal global left-ventricular function. METHODS AND RESULTS: Myocardial blood flow at rest and during pharmacologic vasodilation was measured with (13)N-ammonia PET/CT in mL/g/minute in normal weight control (CON, n = 12), overweight (OW, n = 10), and obese individuals (OB, n = 10). In addition, resting myocardial function was evaluated as circumferential strain (Єc, %) by MRI. Global myocardial flow reserve (MFR) did not differ significantly between CON and OW (2.98 ± 0.96 vs 2.70 ± 0.66, P = .290), whereas it declined significantly in OB (1.98 ± 1.04, P = .030). Further, global Єc (%) was comparable between CON, OW, and OB (-0.24 ± 0.03, -0.23 ± 0.02, and -0.23 ± 0.04) but it was lowest in OB when normalized to the rate-pressure product (NЄc: -0.31 ± 0.06, -0.32 ± 0.05, and -0.26 ± 0.08). When MFR of the three major coronary territories was correlated with corresponding Єc, a positive association was observed in CON (r = 0.36, P = .030), in OW (r = 0.54, P = .002), and also in OB when relating NЄc to coronary vascular resistance during pharmacologic vasodilation (r = -0.46, P = .010). CONCLUSIONS: Higher coronary vasodilator capacity is related to corresponding regional circumferential strain at rest in non-obese individuals, while this is also observed for reduced MFR in obesity.

Anti-apolipoprotein A-1 IgG levels predict coronary artery calcification in obese but otherwise healthy individuals.

We aimed at determining whether anti-apolipoprotein (apo) A-1 IgG levels are independent predictors of coronary artery calcification (CAC) and coronary endothelial dysfunction in obese and nonobese subjects without cardiovascular disease. 48 nonobese and 43 obese subjects were included. CAC score was measured by thorax scanner and defined by an Agatston score > 0. Coronary endothelial dysfunction was determined by measuring myocardial blood flow responses to cold pressor test (CPT) on PET/CT. Serum anti-apoA-1 IgG levels were measured by ELISA. Prevalence of coronary calcification was similar between the two study groups, but the prevalence of coronary endothelial dysfunction was higher in obese subjects. Anti-apoA-1 IgG levels and positivity rate were higher in obese than in nonobese individuals. CAC score was higher in anti-apoA-1 IgG positive subjects. ROC analyses indicated that anti-apoA-1 IgG levels were significant predictors of CAC > 0, but not of coronary endothelial dysfunction with a negative predictive value of 94%. Anti-apoA-1 IgG positivity was associated with a 17-fold independent increased risk of CAC > 0. In conclusion, those preliminary results indicate that anti-apoA-1 IgG autoantibodies are raised in obese subjects and independently predict the presence of coronary calcification in this population but not the presence of coronary endothelial dysfunction.

The influence of insulin resistance, obesity, and diabetes mellitus on vascular tone and myocardial blood flow.

Among individuals with cardiovascular risk factors, reductions in coronary vasodilator capacity with or without diabetes mellitus (DM) carry important diagnostic and prognostic information. Positron emission tomography (PET) myocardial perfusion imaging in concert with tracer kinetic modeling allows the assessment of absolute regional myocardial blood flow (MBF) at rest and its response to various forms of vasomotor stress. Such noninvasive evaluation of myocardial flow reserve (MFR) or the vasodilator capacity of the coronary circulation expands the possibilities of conventional scintigraphic myocardial perfusion imaging from identifying flow-limiting epicardial coronary artery lesions to understanding the underlying pathophysiology of diabetic vasculopathy, microcirculatory dysfunction, and its atherothrombotic sequelae. Invaluable mechanistic insights were recently reported with PET by unraveling important effects of insulin resistance, obesity, and DM on the function of the coronary circulation. Such noninvasive assessment of coronary circulatory dysfunction enables monitoring its response to antidiabetic medication and/or behavioral interventions related to weight, diet, and physical activity that may evolve as a promising tool for an image-guided and personalized preventive diabetic vascular care. Whether PET-guided improvement or normalization of hyperemic MBF and/or MFR will translate into improved patient outcome in DM is a laudable goal to pursue next.

Elevated endocannabinoid plasma levels are associated with coronary circulatory dysfunction in obesity.

AIMS: Aim of this study was to evaluate a possible association between endocannabinoid (EC) plasma levels, such as anandamide (AEA) and 2-arachidonoylglycerol (2-AG), and coronary circulatory function in obesity. METHODS AND RESULTS: Myocardial blood flow (MBF) responses to cold pressor test (CPT) and during pharmacological vasodilation with dipyridamole were measured with (13)N-ammonia PET/CT. Study participants (n = 77) were divided into three groups based on their body mass index (BMI, kg/m(2)): control group 20 ≤ BMI <25 (n = 21); overweight group, 25 ≤ BMI <30 (n = 26); and obese group, BMI ≥ 30 (n = 30). Anandamide plasma levels, but not 2-AG plasma levels, were significantly elevated in obesity as compared with controls, respectively [0.68 (0.53, 0.78) vs. 0.56 (0.47, 0.66) ng/mL, P = 0.020, and 2.2 (1.21, 4.59) vs. 2.0 (0.80, 5.90) ng/mL, P = 0.806)]. The endothelium-related change in MBF during CPT from rest (ΔMBF) progressively declined in overweight and obese when compared with control group [0.21 (0.10, 0.27) and 0.09 (-0.01, 0.15) vs. 0.26 (0.23, 0.39) mL/g/min; P = 0.010 and P = 0.0001, respectively). Compared with controls, hyperaemic MBFs were significantly lower in overweight and obese individuals [2.39 (1.97, 2.62) vs. 1.98 (1.69, 2.26) and 2.10 (1.76, 2.36); P = 0.007 and P = 0.042, respectively)]. In obese individuals, AEA and 2-AG plasma levels were inversely correlated with ΔMBF to CPT (r = -0.37, P = 0.046 and r = -0.48, P = 0.008) and hyperaemic MBFs (r = -0.38, P = 0.052 and r = -0.45, P = 0.017), respectively. CONCLUSIONS: Increased EC plasma levels of AEA and 2-AG are associated with coronary circulatory dysfunction in obese individuals. This observation might suggest increases in EC plasma levels as a novel endogenous cardiovascular risk factor in obesity, but needing further investigations.

Acipimox reduces circulating levels of insulin and associated neutrophilic inflammation in metabolic syndrome.

Metabolic syndrome is a proatherosclerotic condition clustering cardiovascular risk factors, including glucose and lipid profile alterations. The pathophysiological mechanisms favoring atherosclerotic inflammation in the metabolic syndrome remain elusive. Here, we investigated the potential role of the antilipolytic drug acipimox on neutrophil- and monocyte-mediated inflammation in the metabolic syndrome. Acipimox (500 mg) was orally administered to metabolic syndrome patients (n = 11) or healthy controls (n = 8). Serum and plasma was collected before acipimox administration (time 0) as well as 2-5 h afterward to assess metabolic and hematologic parameters. In vitro, the effects of the incubation with metabolic syndrome serum were assessed on human neutrophil and monocyte migration toward the proatherosclerotic chemokine CCL3. Two to five hours after acipimox administration, a significant reduction in circulating levels of insulin and nonesterified fatty acid (NEFA) was shown in metabolic syndrome patients. At time 0 and 2 h after acipimox administration, metabolic syndrome serum increased neutrophil migration to CCL3 compared with healthy controls. No effect was shown in human monocytes. At these time points, serum-induced neutrophil migration positively correlated with serum levels of insulin and NEFA. Metabolic syndrome serum or recombinant insulin did not upregulate CCR5 expression on neutrophil surface membrane, but it increased intracellular JNK1/2 phosphorylation. Insulin immunodepletion blocked serum-induced neutrophil migration and associated JNK1/2 phosphorylation. Although mRNA expression of acipimox receptor (GPR109) was shown in human neutrophils, 5-500 µM acipimox did not affect insulin-induced neutrophil migration. In conclusion, results suggest that acipimox inhibited neutrophil proatherosclerotic functions in the metabolic syndrome through the reduction in circulating levels of insulin.

Coronary artery calcification and cardiovascular risk: the role of RANKL/OPG signalling.

BACKGROUND: Coronary artery disease (CAD) represents the most relevant cause of death and morbidity in the adult population of developed and developing countries. During the last decades, a strong research effort has been performed to identify more selective markers and better assess the cardiovascular risk in both primary and secondary prevention. MATERIALS AND METHODS: This review updates current knowledge regarding the pathophysiological relevance as possible markers of coronary calcification of the receptor activator of nuclear factor-kappa ligand (RANKL)/osteoprotegerin (OPG) system. Furthermore, the potential clinical use of both RANKL/OPG and coronary calcium score (CAC) to assess cardiovascular vulnerability has been discussed. RESULTS: Emerging evidence indicates that atherosclerotic plaque calcification is positively correlated with vulnerability. Several inflammatory mediators have been shown to modulate arterial calcification, thus increasing the risk of plaque rupture. Among these factors, RANKL/OPG axis might be of particular interest as a promising biomarker of plaque vulnerability in subjects with diffuse coronary calcification. CONCLUSION: Together with clinical parameters of coronary calcification (such as CAC), circulating RANKL/OPG levels could contribute to better assess and predict cardiac events.

Structural epicardial disease and microvascular function are determinants of an abnormal longitudinal myocardial blood flow difference in cardiovascular risk individuals as determined with PET/CT.

BACKGROUND: The aim of this study was to determine whether epicardial structural disease may affect the manifestation of a longitudinal decrease in myocardial blood flow (MBF) or MBF difference during hyperemia in cardiovascular risk individuals, and its dependency on the flow increase. METHODS AND RESULTS: In 54 cardiovascular risk individuals (at risk) and in 26 healthy controls, MBF was measured with (13)N-ammonia and PET/CT in mL/g/min at rest and during dipyridamole stimulation. Computed tomography coronary angiography (CTA) was performed using a 64-slice CT of a PET/CT system. Absolute MBFs during dipyridamole stimulation were mildly lower in the mid-distal than in the mid-LV myocardium in controls (2.20 ± .51 vs 2.29 ± .51, P < .0001), while it was more pronounced in at risk with normal and abnormal CTA (1.56 ± .42 vs 1.91 ± .46 and 1.18 ± .34 vs 1.51 ± .40 mL/g/min, respectively, P < .0001), resulting in a longitudinal MBF difference that was highest in at risk with normal CTA, intermediate in at risk abnormal CTA, and lowest in controls (.35 ± .16 and .22 ± .09 vs .09 ± .04 mL/g/min, respectively, P < .0001). On multivariate analysis, log-CCS and mid-LV hyperemic MBF increase, indicative of microvascular function, were independent predictors of the observed longitudinal MBF difference (P ≤ .004 by ANOVA). CONCLUSIONS: Epicardial structural disease and microvascular function are important determinants of an abnormal longitudinal MBF difference as determined with PET/CT.

Inflammation accelerates atherosclerotic processes in obstructive sleep apnea syndrome (OSAS).

Obstructive sleep apnea syndrome (OSAS) is an often underestimated sleep disorder that has been associated with cardiovascular disease. OSAS is characterized by cycles of apnea and/or hypopnea during sleep caused by the collapse of the upper airways. Intermittent hypoxia deriving from the cycles of apnea/arousals (to retrieve the ventilation) plays a pivotal role in the pathogenesis of the disease. Obesity is the most frequent predisposing condition of OSAS. Recent evidence suggests that OSAS could be considered as a pro-atherosclerotic disease, independently of visceral fat amount. Oxidative stress, cardiovascular inflammation, endothelial dysfunction, and metabolic abnormalities in OSAS could accelerate atherogenesis. The present review is focused on the possible pathophysiological mediators which could favor atherosclerosis in OSAS.

A Genetic Polymorphism in the Pannexin1 Gene Predisposes for The Development of Endothelial Dysfunction with Increasing BMI.

Endothelial dysfunction worsens when body mass index (BMI) increases. Pannexin1 (Panx1) ATP release channels regulate endothelial function and lipid homeostasis in mice. We investigated whether the Panx1-400A>C single nucleotide polymorphism (SNP), encoding for a gain-of-function channel, associates with endothelial dysfunction in non-obese and obese individuals. Myocardial blood flow (MBF) was measured by 13N-ammonia positron emission/computed tomography at rest, during cold pressor test (CPT) or dipyridamole-induced hyperemia. Myocardial flow reserve (MFR) and endothelial function were compared in 43 non-obese (BMI < 30 kg/m2) vs. 29 obese (BMI 30 kg/m2) participants and genotyping for the Panx1-400A>C SNP was performed. Groups comprised subjects homozygous for the C allele (n = 40) vs. subjects with at least one A allele (n = 32). MBF (during CPT or hyperemia), MFR and endothelial function correlated negatively with BMI in the full cohort. BMI correlated negatively with MFR and endothelial function in non-obese Panx1-400C subjects, but not in Panx1-400A individuals nor in obese groups. BMI correlated positively with serum triglycerides, insulin or HOMA. MFR correlated negatively with these factors in non-obese Panx1-400C but not in Panx1-400A individuals. Here, we demonstrated that Panx1-400C SNP predisposes to BMI-dependent endothelial dysfunction in non-obese subjects. This effect may be masked by excessive dysregulation of metabolic factors in obese individuals.

Oxaprozin-induced apoptosis on CD40 ligand-treated human primary monocytes is associated with the modulation of defined intracellular pathways.

The modulation of CD40L activity might represent a promising therapeutic target to reduce monocyte inflammatory functions in chronic diseases, such as rheumatoid arthritis. In the present study, we investigated the possible influence of nonsteroidal anti-inflammatory drugs (NSAIDs) on CD40L-induced monocyte survival. Monocytes were isolated from buffy coats by using Ficoll-Percoll gradients. Monocyte apoptosis was evaluated by fluorescence microscopy on cytopreps stained with acridine orange or using flow cytometry analysis of Annexin-V and Propidium Iodide staining. Akt and NF-kappaB activation was assessed using western blot. Caspase 3 activity was determined spectrophotometrically. Among different NSAIDs, only oxaprozin dose-dependently increased apoptosis of CD40L-treated monocytes. Oxaprozin pro-apoptotic activity was associated with the inhibition of CD40L-triggered Akt and NF-kappaB phosphorylation and the activation of caspase 3. In conclusion, our data suggest that oxaprozin-induced apoptosis in CD40L-treated human monocytes is associated with previously unknown cyclooxygenase (COX)-independent pathways. These intracellular proteins might be promising pharmacological targets to increase apoptosis in CD40L-treated monocytes.

Relationship between HDL Cholesterol Efflux Capacity, Calcium Coronary Artery Content, and Antibodies against ApolipoproteinA-1 in Obese and Healthy Subjects.

AIMS: To explore the associations between cholesterol efflux capacity (CEC), coronary artery calcium (CAC) score, Framingham risk score (FRS), and antibodies against apolipoproteinA-1 (anti-apoA-1 IgG) in healthy and obese subjects (OS). METHODS AND RESULTS: ABCA1-, ABCG1-, passive diffusion (PD)-CEC and anti-apoA-1 IgG were measured in sera from 34 controls and 35 OS who underwent CAC score determination by chest computed tomography. Anti-apoA-1 IgG ability to modulate CEC and macrophage cholesterol content (MCC) was tested in vitro. Controls and OS displayed similar ABCG1-, ABCA1-, PD-CEC, CAC and FRS scores. Logistic regression analyses indicated that FRS was the only significant predictor of CAC lesion. Overall, anti-apoA-1 IgG were significantly correlated with ABCA1-CEC (r = 0.48, p < 0.0001), PD-CEC (r = -0.33, p = 0.004), and the CAC score (r = 0.37, p = 0.03). ABCA1-CEC was correlated with CAC score (r = 0.47, p = 0.004) and FRS (r = 0.18, p = 0.29), while PD-CEC was inversely associated with the same parameters (CAC: r = -0.46, p = 0.006; FRS: score r = -0.40, p = 0.01). None of these associations was replicated in healthy controls or after excluding anti-apoA-1 IgG seropositive subjects. In vitro, anti-apoA-1 IgG inhibited PD-CEC (p < 0.0001), increased ABCA1-CEC (p < 0.0001), and increased MCC (p < 0.0001). CONCLUSIONS: We report a paradoxical positive association between ABCA1-CEC and the CAC score, with the latter being inversely associated with PD in OS. Corroborating our clinical observations, anti-apoA-1 IgG enhanced ABCA1 while repressing PD-CEC, leading to MCC increase in vitro. These results indicate that anti-apoA-1 IgG have the potential to interfere with CEC and macrophage lipid metabolism, and may underpin paradoxical associations between ABCA1-CEC and cardiovascular risk.